A method of using a biochip has been known as a method for fixedly attaching biopolymer such as DNAs. In the case of fixedly attaching, for example, DNAs, a DNA probe having a known base sequence is fixedly attached to respective sites of a biochip, then target DNAs having a complementary base sequence by hybridization are bonded to respective sites. By marking the target DNAs bonded by hybridization to respective sites with fluorescent molecules, the amount of bonding of the target DNAs can be recognized as a quantity of fluorescence light.
[Non-patent document: Optical technique “DNA analysis and optical technique” optical technique in life science, Journal of “optics” edited by Toru Makino and kyoichi Kano, Volume 28, No. 10 (1999), (Corp.) Japan Society of Applied Physics, section meeting, Optical Society of Japan, 1999, pp 549-552